The patrons are just leaving a tip commensurate for the time when that $25 meal used to cost $15 (tip not included). Old habits?
In my younger and more affluent days, I felt that a $2 tip was the default mode for the most basic type of customer service (smile and "Thank You" included). When the suggested tip amount got to be 30% in more recent time, service didn't improve, generally. Then came the recession many didn't grow up in, so my tip amounts became more conservative, but I also transitioned into places where tips weren't required. Same basic product, more self-service, a nice utility-dining experience.
Used to be that a nice meal (to me) cost about $15.00+ tip. End result, right at $20.00 for myself. Now those $15.00 meals are close to $20 without the tip. Same service, or worse.
On the other hand, there was one place I used to go. Nice medium-priced local chain. Service was outstanding, usually with the same server. I felt very good having gone there, so I started to increase the amount of the tips, significantly so, to reward the server (hopefully). Usually once a month. After that first time, the server continued the great service. Usually the same server in later visits, too. I was on the radar, and others offered the same outstanding service, for the same higher tip level. But things changed and I couldn't afford that any more, then that original server left, as did the others, it seemed. Back to normal . . .
Applebees noted a while back that after they put the credit card pay kiosks on the individual tables, that tip levels increased to over the suggested amounts. Interesting . . .
CBODY67